Mariosousa millefolia

Wiggins 1964, Benson and Darrow 1981, Turner et al. 1995, Kearney and Peebles 1969

Common Name: milfoil wattle Duration: Perennial Nativity: Native Lifeform: Tree General: Shrub or small tree 1-3 m tall, with slender, sparsely puberulent, but becoming glabrate branchlets and weak, needle-like straight stipular spines 2-3 mm long, ascending and persistent. Leaves: Leaves in 5-10 pairs of pinnae and 20-40 small pairs of leaflets, each 1.5-3 mm long, linear, acute to apiculate, 2-3 mm long; petioles u-shaped in cross section, puberulent but glabrate with age. Flowers: Cream colored flowers in spikes 2.5-5 cm long; flowers sessile, calyx broadly cup-shaped, 0.5-1 mm deep, glabrous or margins ciliolate, petals 2 mm long, glabrous. Fruits: Flat, veiny pods 7-15 cm long, 1-1.8 cm wide, slightly constricted between seeds or margins straight. Ecology: Found in rocky canyons and on hillsides from 4,000-5,500 ft (1219-1676 m); flowers July-September. Distribution: s AZ, sw NM; south to n MEX. Notes: Distinguished as a medium shrub with semi-weak, sometimes whitish, waving branches; small, straight, paired spines at some nodes but otherwise spineless; finely divided bright green leaves with many leaflets; elongated white flower clusters; and wide, flattened pods. Note the nomenclature change for the entire genus. Turner et al. 1995 suggest that A. millefolia may not come much further north than Pima county, a suggestion supported by even collections data. Ethnobotany: Unknown, but other species in this genera have uses. Etymology: Acacia is from Greek akakie taken from ake or akis, -a sharp point, millefolia means many leaved. Synonyms: Acacia millefolia Editor: SBuckley 2010, FSCoburn 2015